Signs of Summer 5: Several Snakes and a Slug

In the abundant growth of the grasses and weeds that we call our “lawns” there are all sorts of unexpected discoveries working their way through the stems and thatch. The ones without legs are particularly notable.

John Mizel Flickr

This summer black rat snakes have been extremely abundant. Down on the Roaring Run Trail, where I ride my bike a couple of times a week, I have had to frequently stop to let three and four foot long black rat snakes make their open slither across the trail from one mowed grass area to the next. There is no pattern as to whether the snakes are heading toward the riverside of the trail or away from it, and no particular time of day at which I see them, but I always stop if there is a snake crossing the trail so that I can direct other bikers and hikers away from it for fear they might accidentally run over or step on the snake. About a month ago, I came upon a group of five walkers clustered together on the trail, talking nervously. There was a black snake in their path and they were afraid to get close to it. I prodded the snake to hurry it along on its way across the trail, and they thanked me for helping them out (and, I am sure, for not making fun of them!). About a half an hour later on my return ride back to the parking lot, the same five walkers were once again stopped in their tracks by a different black snake. The snake seemed to enjoy being the object of the rapt attention of all of those people and did not seem to be in any hurry to get off the trail!

The black rat snake is one the more impressive animals found in the biotic community of Western Pennsylvania. Individuals of this species may reach lengths of 7 to 8 feet and is, thus, the longest snake naturally occurring over its broad, geographic range of the eastern United States (west to Wisconsin and parts of Texas) and southern Ontario. Most typically the dorsum (back) of this species is solid black and the venter (belly) is gray along most of its body length. The gray belly coloration changes into a solid white at the throat. There may also be a series of white spots and speckles running along its sides. There are, however, numerous color variants of this species, and individuals who are gray and even yellow are frequently found. These snakes are very important rodent predators and help to keep our natural ecosystems (and our barns and garages and yards) if not rodent free, then in a rodent balanced state.

A black rat snake with whom I had a long and close relationship was “Strobe” a yellow/brown color variant black rat snake (image, left, D. Sillman). I found Strobe as a tiny, newly hatched snake slithering his way down the lower hallway of the Science Building at Penn State New Kensington. My son, Joe, had expressed interest in have a snake for a pet, so this seemed an excellent opportunity to fill that pet niche for our family. I collected Strobe in a large, Erlenmeyer flask and after a visit to a local pet store, took the “free” snake home with about a hundred dollars of pet snake equipment (habitat, heater, etc.). Joe took excellent care of Strobe for the next six years, and Strobe grew into a very impressive, three foot long, gold-colored, black rat snake. We did learn something very important as we raised Strobe, though: black rat snakes do not make good pets. He never became anywhere close to being tame and would, if an opportunity arose, escape from his expensive habitat box (and hide in the most obscure places of the house (Deborah REALLY loved that!)). He would also grab onto and constrict down on any hands and arms trying to move or feed him and bite those said hands and arms with all of the force he could muster. Now black rat snakes are not poisonous, but they produce an anticoagulant in their saliva that can allow the tiny puncture holes made by their teeth to bleed volumes way out of proportion to the size or depth of the wound!

A biology colleague over in Eastern Pennsylvania heard about Strobe and, since he was interested in the genetics of this non-black coloration of a black rat snake, offered to trade Joe a ball python named “Julius” (which was short for “Julius Squeezer”) for Strobe. Joe accepted and we then had several more, great snake years with the gentle, sweet, very appropriate pet snake, Julius.

Several years ago Jason Bush (our campus’ Director of Business and Finance) and I were out on the Campus Nature Trail looking for two metal surveying plates that marked the boundaries of the campus. I was off the trail on my hands and knees shifting through leaf litter looking for one of the plates when I saw a large diameter black rat snake gliding by. I could only see part of the snake (the rest was hidden in the leaves and ground vegetation), but as I watched the head and the first part of the body slide past I shouted to Jason “I got a three foot black snake down here …. no, it’s more like four feet … no, five … no, more like six!” It was a six and half foot black rat snake with several large bulges in its body which, I am sure, represented recently ingested rodents.

We never did find that plate, by the way!

D. DeStefano

About a month ago I got an email from Danielle DeStefano, whom most of you know as our campus’ Assistant Director of Admissions, but to me she will always be a biology student who has temporally strayed off the path of Truth! Anyway, Danielle sent me an email with an attached photograph of something she saw coming through the grass and across the sidewalk on her way into her office. The photograph is reproduced to the left.
This beauty is a leopard slug (Limax maximus) who was on his way from his nighttime prowling around looking for food to his daylight, sleeping hideout. Leopard slugs are big! They can be four to eight inches long and have gray to brownish-yellow bodies with “leopard-like” streaks of black. They are natives of Europe and have been accidentally transported to places colonized by Europeans (including North and South America, South Africa, Australia, and New Zealand). They are also almost always found near people and their habitations! They mostly eat dead plant materials but can also dine on carrion, fungi, and other slugs. They can also consume young, just sprouting crop plants almost as fast as they can grow! For this reason they are often classified as an agricultural pest.

Leopard slugs can live two and half to three years, and they tend to live alone rather in groups (or in whatever we might call a herd of slugs!). They are hermaphroditic (i.e. have both male and female reproductive organs) but reproduce sexually via some very interesting mating behaviors. A fertilized leopard slug can lay hundreds of eggs (so their population is capable of very rapid growth!).

2 Responses to Signs of Summer 5: Several Snakes and a Slug

Nice bit on the black rat snake. I am in eastern PA and was fishing along the North Branch Susquehanna today 8.31.14. I encountered three black rat snakes. As I explained to my daughter: one is special, two is a coincidence, and three is what’s up with that. I checked their breeding habits and see that was probably not a factor to early and warm for them to be heading to hibernation.

Here is a pic of a leapard slug I found in my backyard last summer 9″+.